How to deal with whitefly on tomato seedlings


Growing tomato seedlings at home, everyone hopes to get strong healthy bushes, which later planted in the ground, will give a bountiful harvest of sweet and tasty fruits. And it is even more insulting to observe how suddenly these bushes start to wither and wither for some reason. Approaching them and examining the bushes of seedlings closer, you do not immediately notice the small annoying butterflies, digging up above the tomatoes. But an experienced gardener immediately realizes that he is dealing with the most dangerous and difficultly infestable pest - the whitefly. And if you do not start the fight against it as soon as possible, then it will be harder and harder to withdraw it.

Pest biology

The whitefly is a small flying insect pest resembling the smallest white moth. They are usually found on the underside of the leaves, and their eggs are usually attached in the same place, and at the same time the larvae look like grayish grains. Insects feed on sap of leaves and stalks of seedlings. No wonder it is often referred to as the “seed moth.” By sucking the juice, the whiteflies release a sticky substance, which is deposited on the upper surface of the lower leaves. It is a favorable environment for the development of black fungi, the so-called black. The leaf surface turns black, and the leaves and shoots themselves dry out and die.

In addition, the whitefly carries a number of very dangerous viral diseases that cause leaf chlorosis, curl, jaundice and are not treatable. They, in turn, cause deformation of shoots and ripening fruits.

Because of the invasion of this harmful moth, you can very quickly lose all the results of your labors, since it multiplies rather quickly. Therefore, the whitefly on tomato seedlings is a terrible disaster and it is necessary to find out how to deal with it. By itself, it will not go anywhere, and after the tomatoes will move to other suitable plants.

To understand how best to deal with whitefly, it is necessary to study its biological features. Firstly, even if you destroy all adults with a powerful insecticide, the struggle will not be over, since no toxic chemicals act on:

  • Eggs protected by a special waxy substance;
  • Insects in the nymph stage, when they stop eating and also become covered with a dense substance (bite).

Life cycle

Usually in the open ground whiteflies lay eggs in the spring, in rooms and greenhouses they can do it all year round. Larvae appear from eggs after a week and begin to look for a convenient place to live. Having found such a place, they turn into nymphs, and, being absolutely immobile for 14 days, remain practically invulnerable to various chemicals. Then they are reborn in adult whiteflies and begin to mate. The full development cycle is 25 days, and the life span of one female is about 30 days. During her life, she has time to lay about 140 eggs.

Whitefly fighting agents

Given the pest's fitness for life in rooms and greenhouses and the difficult life cycle with moments when the whitefly becomes invulnerable, it is necessary to use the whole range of measures in order to end it once and for all.

Chemical methods

For the struggle with adult whitefly flying individuals, chemical control agents are quite effective, but given that it is undesirable to use highly toxic agents in rooms, especially in tomato seedlings, the following drugs are most popular:

  • Aktara - is the best way to protect against whitefly, because it is a systemic drug and has a long period of action (3-4 weeks). Well, the most important thing is that with the Aktara solution, it is not necessary to spray tomato seedlings, it is enough just to spill it thoroughly under the root. It is advisable to repeat the treatment three times with an interval of one week. If you want to try to destroy the whitefly at once, you can try to make a particularly concentrated solution of Aktara, that is, to increase the concentration by 3-4 times. Tomato seedlings will not be harmed, but the whitefly will most likely be finished.
  • Verticillin - this tool is made from spores of the fungus, therefore it is relatively harmless to humans and plants, but is detrimental to the whitefly. About 25 ml per one liter of water is diluted and the resulting solution of tomato seedlings is sprayed twice with an interval of 7-10 days.

In greenhouses it is possible to use other means:

Konfidor, Vertimek, Intavir, Fitoverm, Pegasus, Talstar. There are also hormonal means for the destruction of the eggs and larvae of the whitefly in the greenhouse - the Admiral and Match.

Important! Consider only that they do not act on adults.

Mechanical means

If you are a categorical opponent of the use of chemistry in the house, especially for the treatment of future tomatoes, then to combat the whitefly there are quite effective mechanical means.

Attention! For trapping adult whitefly glue traps are used.

You can take small pieces of plywood, paint them yellow and smear with petroleum jelly or castor oil. Whitefly attracts yellow color and they quickly stick to the surface. Traps can be changed, and you can wipe and lubricate again. The use of ordinary adhesive tapes for flies from whiteflies is also effective.

With a large accumulation of insects on the seedlings, they are quite effectively removed with an ordinary vacuum cleaner.

Regular washing of seedlings with a solution of potash also protects quite well against adult whiteflies.

Biological agents

With large quantities of tomato seedlings, as well as in greenhouses, the method of using predatory and parasitic insects that feed on whitefly larvae and eggs is becoming more popular.

One of these insects are Enkarzia (Encarsia Formosa) and Tricaporus (Encarsia partenopea). On one square meter is enough to release three individuals. The method has an efficiency of up to 98%. It works especially effectively on tomatoes, because the structure of the leaves does not prevent contact of Enkarzia with the larvae of the whitefly.

Another insect representative with which it successfully fights whitefly is the bug Macrolofus. About five bugs are produced per square meter, you can repeat the release after two weeks to consolidate the effect.

Folk remedies

Oddly enough, rather effectively struggling with the whitefly with the help of a variety of herbal infusions. These treatments are absolutely safe for humans and tomato seedlings, but in order for them to be effective against the whitefly, they should be repeated regularly every week until the pest completely disappears. It is desirable to combine the processing of folk and mechanical means. Before using folk remedies, you must first thoroughly atone for the affected tomato seedlings in soapy water to mechanically remove most of the whitefly.

In the first place, of course, is the garlic solution. For its preparation, you must take 150-200 g of garlic, finely grate, add a liter of water and insist 5-7 days. Utensils in which the preparation is made should be very tightly closed. The resulting concentrate is diluted with water - 6 grams per 1 liter of water and damaged tomato seedlings are sprayed with diluted solution.

To combat whitefly use infusion of yarrow. For its preparation, 80 g of yarrow are crushed, poured with a liter of hot water and left to stand in a dark place during the day. After infusion, the solution is filtered and tomato seedlings are treated with it. It is better to wipe the biggest leaves with a napkin dipped in the prepared solution.

Tincture of the roots and leaves of dandelion is also able to help in the integrated fight with the whitefly. In order to prepare it, you need to take 40 g of all parts of the dandelion, pour them with 1 liter of water and insist two hours. After that, the tincture is filtered and you can spray the leaves of tomato seedlings. The drug is practically not stored, so it should be applied immediately after preparation. To enhance the effectiveness of the proposed funds, laundry soap is added to them, which promotes adhesion of drugs to the leaves of tomatoes.

An interesting remedy against whitefly is a solution of the emulsion used in the treatment of scabies. This tool is purchased at the pharmacy. 50 g of the preparation is diluted in a liter of water and damaged tomato bushes are sprayed with an interval of one week.

Prevention of whitefly spread

Attention! Whitefly usually appears with new purchased plants or seedlings.

Theoretically, it can also be brought with the soil that will be infected with its eggs. Therefore, all new plants, as well as purchased seedlings, should be carefully inspected and undergo a mandatory two-week quarantine. The whitefly does not like cold and dies already at a temperature below + 10 ° C. Therefore, it is useful to ventilate the premises from time to time and prevent crowding of the plants. In the greenhouse, the most effective way to prevent it is to fully freeze it in the winter.

With a comprehensive observance of all the above measures to combat whitefly, you can protect your seedlings of tomatoes and get rid of a harmful insect.